Area of ​​a triangle using Heron's formula

The calculator calculates the weighted average of the ratings of the following items.              

Converter allows you to convert numbers between number bases - binary (binary), trójkowym, czwórkowym, Friday, szóstkowym, siódemkowym, octal (octal), dziewiątkowym, decimal (decymalnym) jedenastkowym, dwunastkowym, trzynastkowym, czternastkowym, piętnastkowym, hexadecimal (hex). Typed characters that are not numbers and the letters A, B, C, D, E, F are ignored.      

Calculator by entering an angle in degrees or radians calculated values ​​of the basic trigonometric functions.

Calculator gives the equation line passing through the points specified by the user in the Cartesian coordinate system.          

Checks the calculator is a large number of so-called gay (Happy Number). Number gay is a natural number is defined as follows: Calculate the sum of squares of digits of the number. Repeat this process for the next results as long as we get the number 1 or the results will be repeated. If you have received as a result of one, the original number is the number of gay. Otherwise, a number bleak.